X0508 4 2025-06-09 0001174850 NICOLET BANKSHARES INC NIC 0001253903 ATWELL ROBERT BRUCE C/O NICOLET NATIONAL BANK 111 NORTH WASHINGTON STREET GREEN BAY WI 54301 1 0 Common Stock 2025-06-09 4 M 0 10000 48.85 A 44220 D Common Stock 2025-06-09 4 F 0 6874 119.10 D 37346 D Common Stock 2025-06-09 4 S 0 3126 118.30 D 34220 D Common Stock 339.868 I by Nicolet National Bank Deferred Compensation Plan For Non-employee Directors Stock Option (Right to Buy) 48.85 2025-06-09 4 M 0 10000 0 D 2027-05-16 Common Stock 10000 35000 D The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $118.00 to $118.91, inclusive. Mr. Atwell undertakes to provide to Nicolet Bankshares, Inc., any security holder of Nicolet Bankshares, Inc., or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares at each separate price within the range set forth in footnote (1) to this Form 4. The nonqualified options fully vested as of May 16, 2022. The non-qualified options are exercisable as to 35,000 shares as of the date of this report. /s/ H. Phillip Moore, Jr., as attorney-in-fact for Robert B. Atwell 2025-06-10